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Simultaneous monitoring of profiles of polycyclic aromatic hydrocarbons in contaminated air with semipermeable membrane devices and spruce needles Texto completo
2008
Zhu, Xiuhua | Pfister, Gerd | Henkelmann, Bernhard | Kotalik, Jarmila | Bernhöft, Silke | Fiedler, Stefan | Schramm, Karl-Werner
Gaseous emissions of combusted electronic scrap, PVC, carpet and wood were monitored for polycyclic aromatic hydrocarbons (PAHs) by simultaneous use of semipermeable membrane devices (SPMDs) and shoots of spruce needles (Picea abies). It was found that phenanthrene, acenaphthylene and fluorene were the dominating PAHs in all samples. SPMDs and needles mainly sequestered PAH associated with the vapor phase. Particle-bound PAHs were only detected in small amounts, at which the needles tended to uptake more of these compounds in comparison to the SPMDs. Nevertheless, the logarithm of the concentrations of PAHs analyzed in both passive samplers after the same sampling period exhibited a significant linear correlation with correlation coefficients larger than 0.8073. SPMDs and spruce needles can complement each other in passive air sampling for compounds with a preference to the gas phase rather than aerosols.Relationship of PAHs in SPMDs and spruce needles at the same sampling time was found.
Mostrar más [+] Menos [-]Ozone distribution and phytotoxic potential in mixed conifer forests of the San Bernardino Mountains, southern California Texto completo
2008
Bytnerowicz, Andrzej | Arbaugh, M (Michael) | Schilling, Susan | Frączek, Witold | Alexander, Diane
In the San Bernardino Mountains of southern California, ozone (O(3)) concentrations have been elevated since the 1950s with peaks reaching 600 ppb and summer seasonal averages >100 ppb in the 1970s. During that period increased mortality of ponderosa and Jeffrey pines occurred. Between the late 1970s and late1990s, O(3) concentrations decreased with peaks approximately 180 ppb and approximately 60 ppb seasonal averages. However, since the late 1990s concentrations have not changed. Monitoring during summers of 2002-2006 showed that O(3) concentrations (2-week averages) for individual years were much higher in western sites (58-69 ppb) than eastern sites (44-50 ppb). Potential O(3) phytotoxicity measured as various exposure indices was very high, reaching SUM00 - 173.5 ppmh, SUM60 - 112.7 ppmh, W126 - 98.3 ppmh, and AOT40 - 75 ppmh, representing the highest values reported for mountain areas in North America and Europe.
Mostrar más [+] Menos [-]Susceptibility to acidic precipitation contributes to the decline of the terricolous lichens Cetraria aculeata and Cetraria islandica in central Europe Texto completo
2008
Hauck, M.
The effective quantum yield of photochemical energy conversion in photosystem II (Φ2) was shown to be reduced in the terricolous lichens Cetraria aculeata and Cetraria islandica by short-term exposure to aqueous SO2 at pH values occurring in the precipitation of areas with high SO2 pollution. Significant reduction of Φ2 was found at pH <= 3.3. At pH 2.8, Φ2 was close to zero and did not recover within 24 h. This suggests that sensitivity to SO2 (primarily associated with epiphytic lichens in the past) has contributed to the decline of both species in central Europe. In C. islandica, but not in C. aculeata, thalli with the natural content of lichen substances were more tolerant to SO2 than thalli where the extracellular lichen substances were extracted before the experiment. This supports published results that the depsidone fumarprotocetraric acid, a major lichen substance of C. islandica, increases the pollution tolerance in lichens. Artificial acidic precipitation with aqueous sulphur dioxide at pH 2.8-3.5 affects terricolous Cetraria species.
Mostrar más [+] Menos [-]High-level Zn and Cd tolerance in Silene paradoxa L. from a moderately Cd- and Zn-contaminated copper mine tailing Texto completo
2008
Arnetoli, Miluscia | Vooijs, Riet | Gonnelli, Cristina | Gabbrielli, Roberto | Verkleij, Jos A.C. | Schat, Henk
Cadmium and zinc tolerance were examined in populations of Silene paradoxa, one from uncontaminated calcareous soil (CVD) and one from a mine tailing (FC) (Cd < 1–15 ppm, Zn 400–1300 ppm, pH 2–6). The mine population exhibited extremely high Zn and Cd tolerance levels, although the degrees of Cd and Zn enrichment relatively low at the population site. Cd and Zn hypertolerance in FC were associated with reduced rates of accumulation of these metals, both in roots and shoots (Cd), or exclusively in shoots (Zn). However, exclusion potentially explained only a minor part of the superior tolerance in FC. Cd hypertolerance in FC was associated with decreased, rather than enhanced phytochelatin accumulation. The remarkably high levels of Cd and Zn hypertolerance in FC might relate to the low soil pH, due to oxidation of sulphide minerals, and the absence of soil organic matter at the FC site. Silene paradoxa from a copper mine exhibits extreme levels of Zn and Cd tolerance.
Mostrar más [+] Menos [-]Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China Texto completo
2008
Shi, Guitao | Chen, Zhenlou | Xu, Shiyuan | Zhang, Ju | Wang, Li | Bi, Chunjuan | Teng, Jiyan
A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai.
Mostrar más [+] Menos [-]Effects of prevalent freshwater chemical contaminants on in vitro growth of Escherichia coli and Klebsiella pneumoniae Texto completo
2008
Higgins, J. | Hohn, C.
Many surface and ground waters in the continental US are contaminated with a variety of chemical pollutants, which are usually present in concentrations in the ppm and ppb range. The effects of these pollutants on coliform bacteria, which are prominent members of the aquatic flora, are poorly understood. Using a microtiter plate assay, isolates of Escherichia coli (from chicken intestine and fresh water), and an isolate of Klebsiella pneumoniae (from bovine milk) were exposed to varying concentrations of common pollutants over a 24 h period. The herbicides/pesticides simazine, atrazine, and diazinon; the VOCs trichloroethene and MTBE; the estrogens estradiol and estrone; and caffeine, all failed to inhibit bacterial growth at ppm levels. Only ethylene glycol, and the herbicide 2,4-D, significantly inhibited bacterial growth compared to controls. These results suggest that the replication of coliform bacteria in fresh waters is not adversely impacted by many common pollutants. Using a microtiter plate assay, E. coli and Klebsiella bacteria were exposed to a panel of common chemical pollutants of fresh water; only ethylene glycol and 2,4-D inhibited bacterial replication.
Mostrar más [+] Menos [-]Cellular distribution of metals in a liverwort and in a moss transplanted to two streams of differing acidity. Texto completo
2008
Thiebaut, Gabrielle | Giamberini, Laure | Ghanbaja, Jaafar | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecotoxicité et santé environnementale (ESE) ; Université Paul Verlaine - Metz (UPVM)-Centre National de la Recherche Scientifique (CNRS) | Département de Chimie Physique des Réactions (DCPR) ; Institut National Polytechnique de Lorraine (INPL)-Centre National de la Recherche Scientifique (CNRS)
Cellular distribution of metals in a liverwort and in a moss transplanted to two streams of differing acidity. Texto completo
2008
Thiebaut, Gabrielle | Giamberini, Laure | Ghanbaja, Jaafar | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecotoxicité et santé environnementale (ESE) ; Université Paul Verlaine - Metz (UPVM)-Centre National de la Recherche Scientifique (CNRS) | Département de Chimie Physique des Réactions (DCPR) ; Institut National Polytechnique de Lorraine (INPL)-Centre National de la Recherche Scientifique (CNRS)
International audience | To investigate the consequences of acidification and metal accumulation on the biology of aquatic bryophytes, the acid-tolerant liverwort Scapania undulata (L.) Dum. and the acid-sensitive moss Rhynchostegium riparioides (Hedw.) Cardot were transplanted from one stream to two other streams of differing acidity (pH 5.20 and 6.38). The bryophytes were collected in a circumneutral (pH 6.57) stream in the Vosges Mountains. Metal accumulation was semiquantitatively measured in shoots by energy dispersive TEM X-ray spectroscopy (EDXS). After 1 month, the two species remained green without alteration signs. Although no marked ultrastructural damage was observed in either species, some cells seemed to be necrotic, with flattened chloroplasts, in R. riparioides. Lipid droplet accumulation was observed in some leaf cells of S.undulata when transplanted to the most acidic stream. Metal was mostly localised in the cell wall, and was only sometimes detected in small vacuoles. Under acidic conditions, R. riparioides showed the highest relative amount of Al and the lowest amount of Fe, whereas the acid-tolerant bryophyte species S. undulata contained more Fe and less Al. The capability to limit the uptake of metals into the cytoplasm varies according to the bryophyte species. This could be an explanation of the tolerance of S. undulata to acidification.
Mostrar más [+] Menos [-]Cellular Distribution of Metals in a Liverwort and a Moss Transplanted to Two Streams of Differing Acidity Texto completo
2008
Thiébaut, G. | Giamberini, L. | Ghanbaja, J.
To investigate the consequences of acidification and metal accumulation on the biology of aquatic bryophytes, the acid-tolerant liverwort Scapania undulata (L.) Dum. and the acid-sensitive moss Rhynchostegium riparioides (Hedw.) Cardot were transplanted from one stream to two other streams of differing acidity (pH 5.20 and 6.38). The bryophytes were collected in a circumneutral (pH 6.57) stream in the Vosges Mountains. Metal accumulation was semi-quantitatively measured in shoots by energy dispersive TEM X-ray spectroscopy (EDXS). After 1 month, the two species remained green without alteration signs. Although no marked ultrastructural damage was observed in either species, some cells seemed to be necrotic, with flattened chloroplasts, in R. riparioides. Lipid droplet accumulation was observed in some leaf cells of S.undulata when transplanted to the most acidic stream. Metal was mostly localised in the cell wall, and was only sometimes detected in small vacuoles. Under acidic conditions, R. riparioides showed the highest relative amount of Al and the lowest amount of Fe, whereas the acid-tolerant bryophyte species S. undulata contained more Fe and less Al. The capability to limit the uptake of metals into the cytoplasm varies according to the bryophyte species. This could be an explanation of the tolerance of S. undulata to acidification.
Mostrar más [+] Menos [-]Contamination of urban soils in an area of Northern France polluted by dust emissions of two smelters Texto completo
2008
Douay, Francis | Pruvot, Christelle | Roussel, Hélène | Ciesielski, Henri, H. | Fourrier, Hervé | Proix, Nicolas | Waterlot, Christophe | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire d'Analyses des Sols (LAS) ; Institut National de la Recherche Agronomique (INRA)
Water Air Soil Poll 252WD Times Cited:37 Cited References Count:36 | International audience | The contamination of 27 urban topsoils has been assessed around two lead and zinc smelters (Metaleurop Nord and Umicore) in the North of France. Eighteen trace elements have been analysed (Ag, As, Bi, Cd, Co, Cr, Cu, Hg, In, Ni, Pb, Sb, Se, Sn, Tl, Th, U and Zn). The investigation included the study of the vertical distribution of Cd, Pb and Zn as indicators of pollution. It was shown that Cd, In, Pb, Sb and Zn were major pollutants followed in lesser quantities by Ag, Bi, Cu and Hg. In addition, As, Ni, Se, Sn and Tl were present at levels slightly higher than regional agricultural values. The other elements (Co, Cr, Th and U) were at endogenous levels. The observations have highlighted the strong heterogeneity of the physico-chemical parameters of urban soils and the existence of heavy contamination of the under layers by Cd, Pb and Zn. A potential transfer of metals from the topsoil to the deeper layers and especially Cd and Zn, is not excluded. Indeed the soil rework is not the only factor explaining contamination level of the deeper layers of the studied soils. The comparison of the studied element concentrations in urban soils with nearby local agricultural values shows that the dust emission originating from the Metaleurop and Umicore smelters were not the only source of contamination. Thus a large contamination of the studied urban soils by Sb and In could be explained by domestic combustion of coal for heating.
Mostrar más [+] Menos [-]Accumulation of nine metals and one metalloid in the tropical scallop Comptopallium radula from coral reefs in New Caledonia Texto completo
2008
Metian, M. | Bustamante, Paco | Hedouin, L. | Warnau, M.
Uptake of waterborne Cd, Co, Mn and Zn was determined in laboratory experiments using radiotracer techniques (Cd-109, Co-57, Mn-54 and Zn-65). Labelled Zn was mainly accumulated in the digestive gland (65%) and Co in kidneys (81%); Cd and Mn were similarly distributed in digestive gland and gills. In a complementary field study, Ag, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, and Zn were analysed in scallops collected at two stations showing different contamination levels. Digestive gland and kidneys displayed the highest concentrations. Ag, As, Cd, and Fe differed in soft tissues from the two stations, suggesting that Comptopallium radula could be a valuable local biomonitor species for these elements. Low Mn and Zn concentrations found in kidneys suggest that their content in calcium-phosphate concretions differs from the other pectinids. Preliminary risk considerations suggest that As would be the only element potentially leading to exposure of concern for seafood consumers. (c) 2007 Elsevier Ltd. All rights reserved.
Mostrar más [+] Menos [-]Bioaccumulation of persistent organic pollutants in female common dolphins (Delphinus delphis) and harbour porpoises (Phocoena phocoena) from western European seas: Geographical trends, causal factors and effects on reproduction and mortality Texto completo
2008
Pierce, G | Santos, M | Murphy, S | Learmonth, J | Zuur, A | Rogan, E | Bustamante, Paco | Caurant, Florence | Lahaye, V | Ridoux, Vincent | Zegers, B | Mets, A | Addink, M | Smeenk, C | Jauniaux, T | Law, R | Dabin, W | Lopez, A | Farre, J | Gonzalez, A | Guerra, A | Garcia Hartmann, M | Reid, R | Moffat, C | Lockyer, C | Boon, J
Concentrations of polychlorinated biphenyls (PCBs) in blubber of female common dolphins and harbour porpoises from the Atlantic coast of Europe were frequently above the threshold at which effects on reproduction could be expected, in 40% and 47% of cases respectively. This rose to 74% for porpoises from the Southern North Sea. PCB concentrations were also high in southern North Sea fish. The average pregnancy rate recorded in porpoises (42%) in the study area was lower than in the western Atlantic but that in common dolphins (25%) was similar to that of the western Atlantic population. Porpoises that died from disease or parasitic infection had higher concentrations of persistent organic pollutants (POPs) than animals dying from other causes. Few of the common dolphins sampled had died from disease or parasitic infection. POP profiles in common dolphin blubber were related to individual feeding history while those in porpoises were more strongly related to condition. (C) 2007 Elsevier Ltd. All rights reserved.
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